Re: Discussion: The Form Widget use-when attribute

Posted by Adrian Crum on May 07, 2009; 10:13pm
URL: http://ofbiz.116.s1.nabble.com/Discussion-The-Form-Widget-use-when-attribute-tp201454p201458.html

The BeanShell operator overload works after all. I don't know why I was
having a problem with it earlier.

Now that it appears to be working correctly, I have decided against
making this change.

-Adrian

Scott Gray wrote:

> The more I think about it the less I like void values anyway, it just
> increases the likely hood of unintended behavior.  I say we go for it
> and let the exceptions be thrown and then fix them by actually
> initializing the values.
>
> Regards
> Scott
>
> On 5/05/2009, at 5:53 PM, Adrian Crum wrote:
>
>>
>> The UEL throws an exception if an undefined value is used in an
>> expression. I added an extension that allows you to specify a default
>> value if one isn't found. So, it would look like this:
>> ${partyIdfrom$string == ''}.
>>
>> I tried to use the operator overload in BeanShell, but it threw a
>> parse exception. I don't know what that is about.
>>
>> -Adrian
>>
>>
>> --- On Mon, 5/4/09, Scott Gray <[hidden email]> wrote:
>>
>>> From: Scott Gray <[hidden email]>
>>> Subject: Re: Discussion: The Form Widget use-when attribute
>>> To: [hidden email]
>>> Date: Monday, May 4, 2009, 9:51 PM
>>> I don't mind either way, only one question, how does UEL
>>> handle undefined values e.g. (partyIdFrom == void) would we
>>> just do (partyIdFrom == null)?
>>>
>>> It's also worth mentioning that we never needed to use
>>> XML escaping for beanshell it was the one that supported the
>>> method I suggested for UEL.
>>>
>>> Regards
>>> Scott
>>>
>>> On 5/05/2009, at 4:33 PM, Adrian Crum wrote:
>>>
>>>>
>>>> Now that the UEL supports logical operator
>>> substitution
>>> (http://docs.ofbiz.org/display/OFBTECH/Unified+Expression+Language+(JSR-245)+in+OFBiz#UnifiedExpressionLanguage%28JSR-245%29inOFBiz-OperatorSubstitutions)
>>>
>>> we have the ability to eliminate the clumsy XML escaping in
>>> the form widget use-when attribute. The problem is, the form
>>> widget evaluates the use-when attribute with BeanShell, not
>>> UEL.
>>>>
>>>> I would like to change the form widget to use UEL in
>>> use-when expression evaluations. The use-when attribute must
>>> evaluate to a boolean, and UEL is perfect for that. Plus,
>>> expression evaluation using UEL should execute faster than
>>> BeanShell.
>>>>
>>>> The potential downside is the chance there is a
>>> peculiar use-when expression that BeanShell can evaluate,
>>> but UEL can't. Those should be easy to find though.
>>>>
>>>> What do you think?
>>>>
>>>> -Adrian
>>>>
>>>>
>>>>
>>>>
>>>>
>>
>>
>>
>